Grinding-mill roller-mounting



(No Model.)

Patented Apr.28,1891.

WJf/VESSES UNITED STATES PATENT OEEicE..

HENRIT A. DUC, JR., OF CHARLESTON, SOUTH CAROLINA.

GRlNDlNG-IVIILL ROLLER-MOUNTING.

SPECIFICATION forming part of Letters Patent No. 451,392, dated April 28, 1891.

Application filed September 12, 1890. Serial No. 364,711. (No model.)

ToaZZ whom it may concern.-

Bc it known that I, HENRY A. DUC, Jr., of Charleston, in the county of Charleston and State of South Carolina, have invented certain new and useful Improvements in Grinding- Mill Rolleil\lountings; and I do hereby declare that the following is a full, clear, and exact description thereof, reference being had to the accompanying drawings, and to the letters of reference marked thereon,which form part of this specification.

My presentinvention is especially designed for use with crushing orgrinding mills wherein rollers, balls, or cylinders are employed eoacting against a stationary or revolving annulus. It is also applicable to mills wherein the crushing or reducing .of the material is effected by passing it between two or more cylinders or rollers.

The object of the invention is to yieldingly support the rolls independently ot the journal bearings or supports of the rollshat'ts, so

4that the shafts may be, and preferably are,

journaled in fixed or non-yielding bearings, and yet the rolls be so mounted on or attached to the shaft that while securely connected thereto and revolved thereby they can vibrate and alter their position in relation to the shaft, and if necessary assume eccentric and angular positions in relation thereto when subjected vto strain Without displacement of the shaft or its bearings, and will, when the displacing cause is removed, at once resume a proper concentric or normal position with respect to the shaft.

In the accompanying drawings are illustrated various modes of mounting the rolls on the shafts.

Figures l, 2, 3, and 4 arepside elevations of partly-broken shaftsV an d rolls attached thereto by various arrangements of springs. Figs, 5, 6, 7, and 8 are similar views, with the rolls sectioned, of other forms of spring attachments. `Fig.- 9 is a side view of a single spiralspring mounting. Fig. lOis a sectional view showing the springs sprunginto an axial bore of the roll.

The shafts bearing the rolls are mounted in journal-bearings which do not permit the shafts to vibrate or oscillate, but will keep them in the saine plane, and the shafts should be of such stiffness as to sustain the weight of the rolls and the grinding or crushing pressure without yielding or vibration.

In Fig. l the stub-shaft A has two spiral springs B B, rigidly connected to its free end and projecting in the longitudinal plane of the shaft. 'lhe ends of these springs B project through openings in the roll C and are secured thereto, so that normally the roll is held in a position concentric to the shaft A.

Fig. 2 shows the shaft arranged vertically with the roll suspended by the springs from the lower end thereof and adapted to operate against a horizontal annulus D.

Fig. 3 shows a section of a verticaldie-ring or annulus R, with portions of casing of a grinding-mill with shaft A inclined and a conical roller E attached to its end by springs Fig. e illustrates two stub-shafts A A and two sets of spiral springs B B', the crushingroll being supported by the said springs centrally between the ends of shafts A A', which latter revolve in the same axial plane.

Fig. 5 shows the roller mounted between two stub-shafts A A by single coil-springs b b, andshowing it in yielding position in passing over an obstruction or unyielding piece of ore.

Fig. 6 shows the stubshafts A A united by double continuous conically-coiledpiral springs F, which have their central coils f smaller than their main coils. The roller G has a bore g and is secured to the coils by twisting one of the shafts until the spring F at that side is so reduced in diameter that the roll can be slipped thereover onto small coils f. Then by releasing the shaft the spring F resumes its natural size and binds the roller tightly in place. In this case when the roll and shafts are used in the mill they should be revolved in a direction that would tend to unwind the springs, thereby causing the roll to be more tightly gripped.

Fig. 7 illustrates the stub-shafts mounted in ball-and-socket bearings w and deliected while the roller is mounting over a piece of hard substance. The roller in this case may or may not turn angularly to the annulus.

Fig. 8 shows the roll mounted on a series of bow-shaped springs H H, the ends of which are connected to the adjoining ends of stubshafts A A', and Fig. 9 shows the roll mounted lOO' on a continuous single spiral spring passing through the roll.

In Fig. lO the roll I has au annular recess t in its bore, and is secured in position on the spring B by springing the enlarged ends .thereof in the bore fz', the shaft being revolved 1n a direction to expand the springs, thus binding the roll` more tightly. I preferably make the peripheries of the rolls rounding, as shown, so that it' they are turned diagonally to the axle there will still be the same amount of grinding-surface contact between the roll and annulus.

In some instances the springs might bc formed integral with the shafts, The rolls are fastened to the springs, so that they cannot slip thereon in revolving. Obviously various modifications might be iliade iu the mounting of the rolls on the shafts without departing from the spirit of the invention, which is to yieldingly mount the roll on springs independently of the shafts and their journal-bearing mountings, so that the roll can vibrate or shift its position in relation to the shaft, while the latter maintains an undisturbed position. \Vl1en thus mounted, should any hard substance fall between two rolls so mounted or between a roll so mounted and a non-yielding body, the roll would ride up over the substance without displacement of its driving-shaft, and would at once be thrown back into proper grinding or crushing position when the foreign or unyielding substance was passed, thus avoiding injury to the roll and to the shaft, and if such substance be to one side of the roll instead of its center the roll could turn diagonally to the shaft without injury thereto. The supporting-springs must be stiff enough to hold the roll up to grinding position, and the shaft-journals might be made adjustable, so as to throw the roll toward the annulus, thus enabling the grinding-pressure of the roll to be regulated as the springs permit the rolls to revolve eccentrically to the shaft without injury.

In some eases the shaft might be continuous-that is, instead of employing two stubshafts connected by springs, a continuous shaft might be used and the springs be slipped thereovcr. Such construction is indicated in Figs. et and G by dotted lines. In this case the rollerl would necessarily have a bore sufficiently large in diameter to permit its free play and movement by the springs independently of the shaft.

I am aware that dynamos and other rapidly-revolving mechanisms have been mounted on sectional shafts and cushioned by springs,

so that if outof proper alignment the yielding of the shaft would automatically compensate for the non-alignment thereof and cause the body to revolve without jaror trembling; but in my invention I sustain the rolls entirely upon the springs, which are in turn mounted on the shaft; but the latter is non-sectional and is not distorted from a true unbroken axial position, or does not have to be so distorted or deflected in order to enable the roll to pass over irregularities. My invention is not designed to enable the rolls to revolve without jar or to automatically obtain an alignment or compensate for an irregular alignment of the shaft-bearings, but simply to enable the rolls to pass over unyielding pieces of material while grinding, and in so doing, if necessary, to shift to positions eccentric or angular to the shaft without disturbing the lineal truth of the shaft lor detlecting the portion thereof outside the bearings in relation thereto.

Having described my invention, what I claim as new, and desire to secure by Iletters Patent thereon, is-

l. The combination of a stub shaft, a spring secured by one end to one extremity of the shaft and projecting forwardly in the plane of the shaft, constituting a linear continuation thereof and rotated thereby, with a crushing-roll secured to the free end of the spring, supported thereby, and rotated therewith, being thusindirectly connected to, supported on, and driven by the shaft, and yet free to vibrate independently of the latter, substantially as specified.

2. The combination of a Stubshaft, a coiled spring connected to the end thereof and proj ecting therefrom, andaroll having a central bore into which the spring is sprung in order to connect the roll thereto, whereby the roll is caused to rotate with the shaft, but can vibrate independently thereof, substantially as specified,

The combination of opposite stub-shafts, spiral springs secured to the, adjoining ends of said shafts and projecting axially therefrom, and a roll interposed between the said springs, connected thereto, and suspended thereby, all constructed substantially as and for the purpose described.

In testimony that I claim the foregoing as my own I affix my signature in presence of two witnesses.

HENRY A. DUC, JR.

\Vitnesscs:

T. ll. ALEXANDER, S. limsuuitns.

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